A modified polar organic chemical integrative sampler (POCIS) could provide a convenient way of monitoring perfluorinated chemicals (PFCs) in water. In the present study, the modified POCIS was calibrated to monitor PFCs. The effects of water temperature, pH, and dissolved organic matter (DOM) on the sampling rate (R s) of PFCs were evaluated with a static renewal system. During laboratory validation over a 14-day period, the uptake kinetics of PFCs was linear with the POCIS. DOM and water temperature slightly influenced POCIS uptake rates, which is in consistent with the theory for uptake into POCIS. Therefore, within a narrow span of DOM and water temperatures, it was unnecessary to adjust the R s value for POCIS. Laboratory experiments were conducted with water over pH ranges of 3, 7, and 9. The R s values declined significantly with pH increase for PFCs. Although pH affected the uptake of PFCs, the effect was less than twofold. Application of the R s value to analyze PFCs with POCIS deployed in the field provided similar concentrations obtained from grab samples.

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The sorption of perfluorooctanoate (PFOA) onto cyanobacterial biomass is critical to understand its subsequent transport and fate in aqueous environments, but the sorption mechanisms remain largely unknown. This study aimed to investigate the influences of pH, heavy metals, and phosphate on the sorption of PFOA onto cyanobacterial biomass. Results showed that an increase in pH led to a decrease in PFOA sorption, which may be due to electrostatic repulsion. PFOA sorption first decreased, then gradually increased and surpassed the blank in the presence of Pb2+. However, PFOA sorption was suppressed in the presence of Cu2+, Cd2+, and PO43−. The possible mechanisms behind the impacts of pH, heavy metals and phosphate on PFOA sorption were also investigated using Ultraviolet‐visible (UV‐Vis) and Fourier transform infrared (FTIR) spectra. FTIR spectra analysis of the biomass suggested that heavy metal ions can complex with functional groups on the surface of cyanobacteria. Phosphate sorption blocked some of the available sorption sites on the surface of cyanobacteria, which contributed to the decrease in PFOA sorption. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1317–1323, 2016

Municipal solid waste incineration fly ash is classified as hazardous waste because it contains dioxins and a variety of heavy metals. It is not allowed to be directly landfilled without curing pretreatment, but the increasing production of fly ash and scarce land resources has triggered consideration of the rational disposal of fly ash. In this study, solidification treatment and resource utilization were combined, and the detoxified fly ash was used as cement admixture. The effects of thermal treatment in different atmospheres on the physical and chemical properties of fly ash and the effects of fly ash as admixture on cement properties were investigated. The results indicated that the mass of fly ash increased due to the capture of CO2 after thermal treatment in CO2 atmosphere. When the temperature was 500 °C, the weight gain reached the maximum. After thermal treatment (500 °C + 1 h) in air, CO2, and N2 atmospheres, the toxic equivalent quantities of dioxins in fly ash decreased to 17.12 ng TEQ/kg, 0.25 ng TEQ/kg, and 0.14 ng TEQ/kg, and the degradation rates were 69.95%, 99.56%, and 99.75%, respectively. The direct use of fly ash as admixture would increase the water consumption of standard consistency of cement and reduce the fluidity and 28 d strength of mortar. Thermal treatment in three atmospheres could inhibit the negative effect of fly ash, and the inhibition effect of thermal treatment in CO2 atmosphere was the best. The fly ash after thermal treatment in CO2 atmosphere had the possibility of being used as admixture for resource utilization. Because the dioxins in the fly ash were effectively degraded, the prepared cement did not have the risk of heavy metal leaching, and the performance of the cement also met the requirements.